Tile on tile plasterboard

I have a bathroom with two walls tiled, 2300 x 1500 & 750 x 1500 The main wall is plasterboard partition. I want to freshen up the bathroom but don't want to go as far as ripping everything out. I have seen a clip on utube about tiling over tiles using silicone adhesive. Is it possible to use this on plasterboard, will it depend on size, weight of tiles?